<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Document</title>
  </head>
  <body>
    <div class="space"></div>
    <div class="sun"></div>
  </body>
  <style>
    body {
      background-color: #000;
    }
    @keyframes spaceChange {
      from {
        opacity: 0.3;
      }
      25% {
        opacity: 1;
      }
      50% {
        opacity: 0.3;
      }
      75% {
        opacity: 0.1;
      }
      to {
        opacity: 0.3;
      }
    }
    .space {
      animation: spaceChange 10s cubic-bezier(0.5, 0, 0.5, 1);
      height: 800px;
      background-image: linear-gradient(to bottom, rgba(0, 130, 255, 1), #fff);
    }
    @keyframes sunRise {
      from {
        opacity: 0;
        transform: translate(-50%, -50%) scale(0.5, 0.5) translateX(0)
          translateY(-400px);
      }
      10% {
        opacity: 0.1;
        transform: translate(-50%, -50%) scale(0.5, 0.5) translateX(0)
          translateY(-300px);
      }
      20% {
        opacity: 0.5;
        transform: translate(-50%, -50%) scale(0.5, 0.5) translateX(0)
          translateY(-200px);
      }
      30% {
        opacity: 1;
        transform: translate(-50%, -50%) scale(0.5, 0.5) translateX(0)
          translateY(0px);
      }
      50% {
        opacity: 0;
      }
      to {
        opacity: 0;
      }
    }
    .sun {
      animation: sunRise 10s;
      position: absolute;
      left: 50%;
      top: 50%;
      transform: translate(-50%, -50%) scale(0.5, 0.5);
      width: 50px;
      height: 50px;
      background-color: #fff;
      border-radius: 50%;
      box-shadow: 0px 0px 100px 50px #fff, 0px 0px 250px 125px #ff0;
    }
  </style>
</html>
